by Liz Szabo, USA TODAY

by Liz Szabo, USA TODAY

About 29% of white high school girls use tanning beds, according to a new study, whose findings have alarmed doctors and public health officials concerned about rising rates of deadly skin cancers in young women.

The evidence linking the ultraviolet light from tanning lamps with melanoma has never been stronger, says Len Lichtenfeld, deputy chief medical officer at the American Cancer Society, who wasn't involved in the new study. Melanoma is a lethal form of skin cancer diagnosed in nearly 77,000 Americans a year, according to the cancer society. Melanoma kills 9,500 Americans a year.

Since 1992, rates of melanoma - once considered an old person's disease - have risen 3% a year in white women ages 15 to 39, according to the cancer society.

Indoor tanning rates increase steadily as girls move through high school, peaking around age 18. By that age, 44% of white girls have used a tanning salon in the past year and 30% were frequent tanners, using the facilities 10 or more times in that period, according to the new study from the Centers for Disease Control and Prevention, published in JAMA Internal Medicine.

Preliminary research in recent years suggests that ultraviolet radiation may have addictive properties, which could explain why some people use tanning salons so often.

About 25% of white women ages 18 to 34 also have used a tanning bed in the past year, although indoor tanning steadily becomes less popular as adult women age, the new study found.

"It's very disturbing," Lichtenfeld says.

These young women are dramatically boosting their cancer risk, says Sophie Balk, an attending pediatrician at the Children's Hospital at Montefiore in Bronx, N.Y., who wasn't involved in the new study.

Using a tanning bed before age 35 increases melanoma risk by up to 75%, while using one before age 25 increases the risk of non-melanoma skin cancer by up to 100%, according to an analysis of earlier studies published last year in the journal BMJ. The same meta-analysis found that melanoma risk increases 1.8% with each tanning session per year.

This grim message is apparently lost on girls preparing for senior proms and graduations, Lichtenfeld says. Indoor tanning has grown into a $5 billion a year industry. Nearly 20,000 tanning salons operate across the USA, according to a report by IBISWorld,which publishes research on a variety of industries.

"Young people often think they're not susceptible to harm from risky behaviors," says Balk, who wrote the American Academy of Pediatrics policy report on tanning, called "Ultraviolet Radiation: A Hazard to Children and Adolescents."

Even adults often fail to realize the dangers of tanning, Balk says.

"Young teens sometimes have their first tanning experience with their moms," Balk says. For pediatricians, "it's important for us to discuss the dangers with parents as well as teens."

The CDC study was based on the 2011 National Youth Risk Behavior Survey and the 2010 National Health Interview Survey.

In a statement, the American Suntanning Association, which represents tanning salon owners, objects to targeting safety campaigns at young women.

"CDC's short letter in JAMA calls for policy action, but in doing so ignores mountains of conflicting and confounding data which support teaching sunburn prevention to people of all ages, instead of targeting sun abstinence campaigns at young women. It could not be any more clear that skin cancer rates are skyrocketing in men, and particularly men over age 50, but CDC has inexplicably ignored this group."

The dangers of tanning beds have led to increased restrictions in recent years.

The International Agency for Research on Cancer, affiliated with the World Health Organization, now classifies ultraviolet tanning bed lamps as carcinogens. The Indoor Tanning Association, an industry group representing manufacturers of tanning devices, disputes the research behind the cancer agency's ruling.

Brazil and the state of New South Wales in Australia have banned indoor tanning completely, while France, Germany and the United Kingdom have made it illegal for teens.

Six states -- California, Vermont, Oregon, Nevada and Texas -- have banned indoor tanning for minors, and 33 states have some restrictions on tanning by teens, Balk says. Last week, Illinois legislators passed a ban on under-age tanning, as well.

The American Academy of Pediatrics and other medical groups have called for a nationwide ban on tanning by children and adolescents.

Yet many children can still get access to tanning beds, according to a study published in February in Pediatrics. Researchers interviewed tanning salon employees in Missouri, which doesn't restrict minors' use of these facilities. Authors found that more than two-thirds of employees would allow children as young as ages 10 to 12 to tan, some without parental consent. More than 40% of tanning salon employees surveyed said there were no health risks to tanning.

In May, the Food and Drug Administration proposed stricter regulations for tanning beds, which today are included in the same low-risk category of tongue depressors, Band-Aids and other devices. Under the proposed change, tanning lamps would have to include warning labels alerting customers to the risk of skin cancer and noting that they should not be used by people under 18.

The Indoor Tanning Association has said it is "concerned that the proposed requirements will burden our members with additional unnecessary governmental costs in an already difficult economic climate."

The Indoor Tanning Association also opposed a 10% tax on tanning services, created by the Affordable Care Act in 2010. The Obama administration estimates the tax will raise $2.7 billion over the next decade.